1. Field of the Invention
This invention relates to a tandem roadwheel system as employed on a vehicle, especially a construction vehicle such as a motor grader.
2. Prior Art
A motor grader is oft times operated on uneven terrain whereby the tandem roadwheels on one lateral side of the vehicle are placed vertically below the tandem roadwheels mounted on the opposite side of the vehicle. Also, the tandem roadwheels on one side of the vehicle may individually be placed at different vertical positions because one of the roadwheels may be riding over a rock, dipping into a ditch or the like. The resulting tilting of the vehicle may thus give rise to operational problems such as reduced tractive effort of the vehicle and a reduction in drawbar pull. In addition, conventional tandem mounted rubber tires employed on conventional motor graders essentially function as undampened springs which do not provide the suspension properties desired for earthworking operations. Further, equal roadwheel loading is generally not provided under all conditions in a motor grader. Still further, motor graders normally do not provide means for levelling the main frame and operators station structure when the vehicle is traversing an angled side slope for the purpose of grading same. This causes operator discomfort and reduced control with resulting decreased productivity.